Published online before print June 20, 2003, 10.1148/radiol.2282012162
(Radiology 2003;228:430-435.)
© RSNA, 2003
Thoracic Involvement of Type A Aortic Dissection and Intramural Hematoma: Diagnostic Accuracy—Comparison of Emergency Helical CT and Surgical Findings1
Satoru Yoshida, MD,
Hidenari Akiba, MD,
Mitsuharu Tamakawa, MD,
Naoya Yama, MD,
Masato Hareyama, MD,
Kiyofumi Morishita, MD and
Tomio Abe, MD
1 From the Departments of Radiology (S.Y., H.A., M.T., N.Y., M.H.) and Cardiovascular Surgery (K.M., T.A.), Sapporo Medical University, School of Medicine, Japan. From the 1999 RSNA scientific assembly. Received January 14, 2002; revision requested March 5; final revision received September 9; accepted December 10. Address correspondence to S.Y., Department of Radiology, Muroran City General Hospital, Yamate-chou 3-8-1, Muroran 051-8512, Japan (e-mail: satyoshi@chive.ocn.ne.jp).
 |
ABSTRACT
|
|---|
PURPOSE: To assess the accuracy of various findings at emergency helical computed tomography (CT) for the evaluation of thoracic involvement of type A aortic dissection (AD) and type A intramural hematoma (IMH) and to compare these findings with those at surgical confirmation.
MATERIALS AND METHODS: Fifty-seven patients with acute chest pain underwent emergency helical CT and subsequent surgery for type A AD or IMH. Patients in whom AD or IMH was detected in three segments of the thoracic aorta or those in whom there was a site of any entry tear, arch branch vessel involvement, pericardial effusion, or aortic arch anomaly were examined at helical CT. Sensitivity, specificity, and accuracy of helical CT, along with 95% CIs, were calculated by using surgical confirmation as the reference standard.
RESULTS: For the detection of AD or IMH of the thoracic aorta, the accuracy of helical CT was 100%. The sensitivity, specificity, and accuracy, respectively, were 82%, 100%, and 84% for an entry tear; 95%, 100%, and 98% for arch branch vessel involvement; and 83%, 100%, and 91% for pericardial effusion. These values were all 100% for aortic arch anomalies.
CONCLUSION: Emergency helical CT of the thorax depicts findings that are highly accurate in the evaluation of acute type A AD and IMH.
© RSNA, 2003
Index terms: Aorta, CT, 56.12111, 56.12112, 56.12115 • Aorta, dissection, 56.74 • Computed tomography (CT), helical, 56.12111, 56.12112, 56.12115
|
INTRODUCTION
|
|---|
Acute aortic dissection (AD) is a cardiovascular emergency that requires prompt diagnosis and treatment (1). For therapeutic and prognostic reasons, AD that involves the ascending aorta is classified as Stanford type A regardless of the site of the intimal tear, and AD that does not involve the ascending aorta is classified as Stanford type B (2). In a collective review of patients with acute AD involving the ascending aorta (type A) who did not undergo surgery, the mortality was reported to be 38%, 50%, and 70% within 1, 2, and 7 days, respectively (3). The major cause of early death was aortic rupture into the pericardial or pleural cavity. Intramural hematoma (IMH) may be an early stage or a variant of AD (4–8). Many investigators distinguish between AD and IMH, depending on the presence or absence of an intimal flap (8). The Stanford classification is applied to IMH, as well as to AD; designation of type A IMH means IMH that involves the ascending aorta (4–8). Some investigators have stated that early surgical repair should be considered for patients with type A IMH (6–8). In contrast, the majority of patients with uncomplicated type B IMH and type B AD can be treated successfully with medical therapy. Therefore, especially in type A AD and type A IMH, accurate diagnosis is urgently needed. A single valuable diagnostic procedure might be preferable to a stepwise diagnostic approach. Time is very important for diagnosis and treatment of patients with acute type A AD; any delay in further diagnostic evaluation before surgery should be avoided, because it is difficult to predict when acute type A AD will rupture.
Currently, a wide range of emergency conditions can be quickly and accurately diagnosed with helical CT (9). Findings in many investigations have proven the accuracy of enhanced helical CT in the detection of AD (10–16). The purpose of this study was to assess the accuracy of emergency helical CT for the evaluation of thoracic involvement of type A AD and type A IMH and to compare CT findings with surgical findings.
|
MATERIALS AND METHODS
|
|---|
Subjects
Between April 1992 and October 1999, 139 patients who were suspected of having acute AD or IMH were admitted to our hospital. Emergency helical CT was performed in 121 patients; the other 18 patients had cardiopulmonary arrest at arrival or died suddenly. Of these 121 patients, 58 had CT findings of type A AD or type A IMH. We did not enroll a patient with type A IMH at CT because she refused to undergo surgery. We therefore enrolled 57 patients (35 men, 22 women; age range, 31–85 years; mean age, 55 years) with type A AD or IMH. At surgery, 45 patients had type A AD and 12 had type A IMH. Subtypes were as follows: DeBakey type I, including an entry tear in the aortic arch (n = 26); DeBakey type II (n = 8), retrograde dissection from DeBakey type IIIB (n = 17); and no entry tear (n = 6). All patients had had a sudden onset of chest pain during the preceding 48 hours. The medical history was relevant for four patients who had a history of Marfan syndrome and two who had experienced Stanford type B AD in the past. Main surgical procedures were ascending aorta replacement (n = 5), Bentall operation (n = 3), total arch replacement (n = 5), ascending aorta plus total arch replacement (n = 39), and Bentall operation plus total arch replacement (n = 5). Additional procedures were coronary artery bypass graft (n = 2), aortic valve resuspension (n = 7), and elephant trunk reconstruction (n = 10).
Verbal informed consent was obtained from all patients, and written informed consent was obtained from their families or relatives in emergencies after the nature of the procedures had been fully explained. This study was conducted in accordance with the Declaration of Helsinki principles; our institutional review board did not require its approval for this study.
Imaging Technique
The helical (spiral) CT examinations were performed by using scanners (Somatom Plus-S; Siemens, Erlangen, Germany), with a maximum continuous scanning time of 40 seconds. Each examination began with unenhanced CT of the thorax by using 5-mm collimation and a 5–10-mm intersection gap to screen the thoracic lesion and to detect any cuff or crescent of high attenuation indicative of IMH, internal displacement of intimal calcifications, or acute hemorrhage in the mediastinum. Before beginning the helical CT study, the patients practiced breath holding to minimize the motion artifacts and diaphragmatic excursion. Helical scanning was performed to include an area from the lung apex to the groin during bolus injection of contrast material. Contrast material (ioversol, Optiray 240; Mallinckrodt, St Louis, Mo) was injected at a rate of 2 mL/sec through the right arm vein by using a power injector (Angiomat CT; Liebel-Florsheim, Cincinnati, Ohio). Nonionic contrast material (240 mg of iodine per milliliter; total volume of 150 mL; 75 mL per scan) was used. The scanning delay was 30 seconds. The first half of the spiral acquisition, mainly in the thoracic aorta, was obtained within 30 seconds or less of breath holding. The interscanning delay was 15–20 seconds to allow the x-ray tube to cool and the patient to respire. The latter half of spiral acquisition, mainly in the abdominal aorta, was obtained by using the same settings as were used to obtain the first scan. The scanning parameters were collimation of 5 mm and table speed of 7–10 mm/sec. Data were reconstructed with a 180-line interpolation algorithm. Scans were reconstructed at 5-mm intervals in transverse planes. Multiplanar reconstruction was performed with standard scanner software (Somatom Plus-S; Siemens Medical Solutions, Forchheim, Germany) in only five questionable cases to confirm the correct location of an entry tear on the scan obtained at emergency helical CT. The time from chest pain onset to emergency helical CT ranged from 30 minutes to 48 hours (median, 5.0 hours), and the time from helical CT to surgery ranged from 1 to 360 hours (median, 6.0 hours). Preoperative emergency angiography was performed in only nine patients between 1992 and 1995. All underwent transthoracic echocardiography for the evaluation of aortic regurgitation and left ventricular function.
There were no complications related to helical CT in any of these cases; there were no nondiagnostic examinations due to motion artifacts, because all patients were able to hold their breath.
Image Interpretation
At the time that CT was performed, findings at helical CT were interpreted before surgery with the consensus of two inconstant (due to the emergency setting) readers (ie, authors) who were experienced radiologists and cardiovascular surgeons and who were blinded to the findings of other imaging modalities but were aware of the patients’ clinical histories. The criteria that had previously been reported for the diagnosis of AD and IMH were used in the CT interpretation (4–7,9–22). The typical feature of AD at enhanced CT is a well-defined partition (ie, intimal flap) between the true and false lumina within the aorta. IMH is characterized by the absence of an intimal flap and direct flow communication between the true and false lumina. Its characteristic findings are a cuff or crescent of high attenuation and internal displacement of intimal calcification at unenhanced CT and aortic wall thickening without evidence of an intimal flap at enhanced CT (4–7,16). An entry tear was defined as the most proximal split in the intimal flap or an ulcerlike projection within the IMH at enhanced CT. The presence or absence of AD and IMH in three segments of the thoracic aorta (ie, ascending aorta, aortic arch, and descending aorta), the site of an entry tear, arch branch vessel involvement, pericardial effusion, and aortic arch anomalies were examined by using helical CT. No attempt was made to assess aortic regurgitation or coronary artery involvement with helical CT. Inspection of the aorta and adjacent tissues at surgery was performed by experienced surgeons; findings were noted and recorded on the surgical report.
Retrospectively, all helical CT images were reevaluated by a radiologist (S.Y.) at a second unblinded reading to analyze the causes of false-negative or false-positive findings.
Statistical Analysis
The sensitivity, specificity, and accuracy of helical CT for each parameter evaluated were calculated, along with 95% CIs, by using the surgical findings as the reference standard. With TN as true-negative findings, TP as true-positive findings, FN as false-negative findings, and FP as false-positive findings, sensitivity was calculated as TP/(TP + FN), specificity was calculated as TN/(TN + FP), and accuracy was calculated as (TP + TN)/(TP + FN + TN + FP).
|
RESULTS
|
|---|
In the detection of AD or IMH in the ascending aorta, the sensitivity and the accuracy of helical CT were 100% (57 of 57). In the detection of AD or IMH in the aortic arch or the descending aorta, the sensitivity, specificity, and accuracy of helical CT were 100% (49 of 49), 100% (eight of eight), and 100% (57 of 57), respectively. The diagnosis in all 57 patients was correct as type A AD (n = 45) or IMH (n = 12) at helical CT (Figs 1, 2). A perivenous streak artifact or an aortic pulsation artifact did not influence the detection of type A AD or IMH in any patient. For diagnosis of IMH, unenhanced CT showed a cuff or crescent of high attenuation (n = 12) and internal displacement of intimal calcification (n = 5).
View larger version (134K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 1. Type A AD in a 69-year-old woman. Transverse enhanced helical CT scan demonstrates intimal flap (arrowheads) within the ascending and descending aorta, large entry tear (arrow) in the ascending aorta, and bilateral pleural effusion. Entry tear was defined as a split in the intimal flap. Diagnosis of type A (ie, DeBakey type I) AD was confirmed at surgery.
|
|
View larger version (150K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2a. Type A IMH in a 48-year-old man. (a) Transverse unenhanced CT scan shows cuff of high attenuation (white arrow) within the ascending aorta, internal displacement of intimal calcifications (arrowheads) in the ascending and descending aorta, and pericardial effusion (black arrow). (b) Transverse enhanced helical CT scan clearly demonstrates type A IMH (arrow). Diagnoses of type A IMH and no entry tear were confirmed at surgery.
|
|
View larger version (151K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2b. Type A IMH in a 48-year-old man. (a) Transverse unenhanced CT scan shows cuff of high attenuation (white arrow) within the ascending aorta, internal displacement of intimal calcifications (arrowheads) in the ascending and descending aorta, and pericardial effusion (black arrow). (b) Transverse enhanced helical CT scan clearly demonstrates type A IMH (arrow). Diagnoses of type A IMH and no entry tear were confirmed at surgery.
|
|
The results of the other evaluation are shown in the Table. For the detection of an entry tear, the major causes for false-negative findings were a small entry tear, an aortic pulsation artifact, and an artifact caused by catheter or venous enhancement (Figs 3, 4). At surgery, six patients with IMH had a small entry tear and six with IMH did not have any entry tear. Helical CT demonstrated an entry tear within the IMH in five patients (Fig 5). In the evaluation of arch branch vessel involvement, the accuracy of helical CT was 98%. At surgery, 19 patients had arch branch vessel involvement (18 with type A AD and one with type A IMH that converted into type A AD after 29 hours); seven had one-vessel lesions, four had two-vessel lesions, and eight had three-vessel lesions (Fig 6). The locations were the brachiocephalic artery (n = 17), the left common carotid artery (n = 10), and the left subclavian artery (n = 12). The cause of the one false-negative finding at helical CT was a short dissection of a branch. In the detection of pericardial effusion, the accuracy of helical CT was 91%. The false-negative findings may have been caused by the delay between helical CT and surgery (because of the progressive nature of the disease) rather than by helical CT itself. In two cases, helical CT showed a small pericardial effusion only in the anterosuperior recess of the pericardial sac, which was later confirmed during the surgical operation. In the depiction of aortic arch anomalies, the accuracy of helical CT was 100%. Three patients had aortic arch anomalies: one had an aberrant right subclavian artery; another, a left vertebral artery originating from the aortic arch; and the last, both of these anomalies. However, no direct involvement of dissection into these four arteries was observed at helical CT or during the surgery.
View larger version (122K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 3. Type A AD in a 69-year-old man. Transverse enhanced helical CT scan demonstrates intimal flap (open arrow) and entry tear (arrow) in the ascending aorta. There was a high-attenuation fluid collection (arrowhead) in the anterosuperior pericardial recess (ie, superior sinus), and this finding indicated recent hemopericardium. Diagnoses of type A (ie, DeBakey type I) AD and bloody pericardial effusion were confirmed at surgery.
|
|
View larger version (109K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4a. Type A AD in a 48-year-old man. (a) Transverse enhanced helical CT scan shows entry tear (arrow) in the aortic arch. (b) Coronal and (c) sagittal reformations clearly show entry tear (arrow) in the aortic arch proximal to the origin of the left subclavian artery. At surgery, entry tear was confirmed in the aortic arch, and graft replacement of the ascending aorta and total aortic arch was performed.
|
|
View larger version (99K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4b. Type A AD in a 48-year-old man. (a) Transverse enhanced helical CT scan shows entry tear (arrow) in the aortic arch. (b) Coronal and (c) sagittal reformations clearly show entry tear (arrow) in the aortic arch proximal to the origin of the left subclavian artery. At surgery, entry tear was confirmed in the aortic arch, and graft replacement of the ascending aorta and total aortic arch was performed.
|
|
View larger version (136K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4c. Type A AD in a 48-year-old man. (a) Transverse enhanced helical CT scan shows entry tear (arrow) in the aortic arch. (b) Coronal and (c) sagittal reformations clearly show entry tear (arrow) in the aortic arch proximal to the origin of the left subclavian artery. At surgery, entry tear was confirmed in the aortic arch, and graft replacement of the ascending aorta and total aortic arch was performed.
|
|
View larger version (130K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 5a. Type A IMH in a 75-year-old man. (a) Transverse enhanced helical CT scan at the level of the aortic arch shows a small entry tear (arrow), which appears as an ulcerlike projection, within IMH in the upper descending aorta distal to the origin of the left subclavian artery. (b) Transverse enhanced helical CT scan at the level of the main pulmonary artery shows type A IMH with mediastinal hemorrhage (arrow). At surgery, entry tear was confirmed in the descending aorta.
|
|
View larger version (133K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 5b. Type A IMH in a 75-year-old man. (a) Transverse enhanced helical CT scan at the level of the aortic arch shows a small entry tear (arrow), which appears as an ulcerlike projection, within IMH in the upper descending aorta distal to the origin of the left subclavian artery. (b) Transverse enhanced helical CT scan at the level of the main pulmonary artery shows type A IMH with mediastinal hemorrhage (arrow). At surgery, entry tear was confirmed in the descending aorta.
|
|
View larger version (119K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 6. Type A AD in a 67-year-old man with a faint left radial pulse, which shows diminution. Transverse enhanced helical CT scan shows arch branch vessel involvement of dissection (arrowheads) into three vessels. These findings were confirmed at surgery.
|
|
|
DISCUSSION
|
|---|
The initial results showed that conventional CT was not perfectly accurate for diagnosing AD because the temporal resolution was insufficient (17–22). In an article by Nienaber et al (22), the authors found that conventional CT had a sensitivity of only 82.6% for type A AD. Helical (or spiral) CT is the most important radiologic development in the past decade and is now considered to be one of the most valuable tools in the diagnosis of emergency conditions in patients (9). Today, most emergency hospitals in Japan are equipped with helical CT scanners that are available for emergency cases 24 hours a day, 7 days a week. Emergency helical CT is a safe reliable imaging tool for evaluation of patients who are suspected of having acute type A AD. Accuracy is high with helical CT of the thorax not only in the detection of AD or IMH but also in the assessment of the extent of its involvement. The high accuracy of helical CT in our results was dependent on a knowledge of the pitfalls in the diagnosis of AD or IMH (23,24). An aortic motion artifact at transverse enhanced helical CT sometimes simulates a type A IMH. However, multiplanar reconstruction of images obtained at enhanced helical CT and or unenhanced CT provides evidence of motion artifacts. Ledbetter et al (16) emphasized the importance of obtaining unenhanced CT scans prior to contrast administration for the detection of IMH. We think that the combined use of unenhanced CT and enhanced helical CT is useful for correct diagnosis of acute IMH. Perivenous streak artifacts did not influence the diagnosis of type A AD or IMH in any of our cases, because the orientation of such artifacts typically varies from section to section and extends beyond the outline of the aortic wall. We tried to minimize perivenous streak artifacts with injection of the contrast material into a right arm vein at a rate of 2 mL/sec. Some authors (14) advocate injection into a leg vein, but this technique has not gained widespread use in Japan.
The definition of IMH varies, depending on the investigators (4–8,16). We use the term IMH to represent a condition characterized by clotted intramural blood with or without a visible entry point in an emergency setting, and possibly an early stage or variant of AD, whereas others use the term in cases of penetrating atherosclerotic ulcer. This results in confusion. Sometimes, a penetrating atherosclerotic ulcer with IMH may occur in a nonemergent or nondissection setting. Penetrating atherosclerotic ulcer usually involves the middle to distal descending aorta and is therefore easily distinguished from type A AD or type A IMH. Rarely, type B dissection can occur as a late complication of penetrating atherosclerotic ulcer (16).
The correct identification of an entry tear is important for the surgical procedure, because surgery in type A dissection consists of graft replacement of the affected thoracic aorta, including an entry tear (1). The location of an entry tear influences the surgical procedure through a median sternotomy, especially in type A AD with an entry tear in the aortic arch or descending aorta. Any remnant entry tear may increase the possibility of enlargement of the false lumen as a late complication. Nienaber et al (22) commented that CT was the only inappropriate method for locating the entry site. In contrast, our results indicated that helical CT was accurate in detection of the entry site. This discrepancy may be due to the difference between conventional and helical CT. However, it is possible that small intimal tears could have been missed with helical CT performed with our parameters.
Sommer et al (12) reported that, for helical CT, sensitivity was 93% and specificity was 97% in the assessment of supraaortic branch involvement, and these findings are in general agreement with our findings. Moreover, they stated that knowledge of the involvement of supraaortic branches may facilitate planning of aortic surgery. At surgery for total arch replacement, it is very important to recognize preoperatively anatomic details of the aortic arch and its branches, such as involvement of dissection and congenital arch anomaly. We consider that no other examinations are needed for this purpose in emergency situations.
The anterosuperior recess (superior sinus) is an upper portion of the pericardial sac located in front of the ascending aorta and pulmonary arterial trunk. Baque-Juston et al (25) commented that an obviously enlarged anterosuperior recess seen on a CT scan may be an early sign of a small pericardial effusion. Our experience supports this comment, and it is therefore important for the detection of a small pericardial effusion to evaluate the anterosuperior recess, even if CT shows a normal circumferential pericardial thickness.
Helical CT of the thorax is useful for the evaluation of aortic arch anomalies (14). Although the association of acute type A AD and aortic arch anomalies is rare, correct diagnosis of the former before surgery is very important (26,27). We believe that radiologists must play an important role in the detection of these anomalies at emergency helical CT.
Angiography has been considered the standard for the diagnosis of AD, but sensitivity or specificity is not 100% (20). The major disadvantages of angiography are cost, failure to detect IMH, and excessive time required for the examination. In a recent report, it was stated that routine angiography may increase mortality because of the imposition of an unnecessary delay before an emergency surgical operation in a patient with type A AD (28). We agree with their main message. Performance of helical CT in those patients who are suspected of having AD can be substantially less costly when compared with performance of angiography.
We believe that once a diagnosis of acute type A AD has been established on the basis of findings at helical CT, the patient should be transferred to the operating room immediately. Transesophageal echocardiography can be performed safely after intubation in the operating room, where anesthesia and surgery are available. Nienaber et al (22) commented that transesophageal echocardiography in unstable patients should be considered the optimal approach for detection of AD of the thoracic aorta. However, Geibel et al (29) reported that 77% of 51 patients who were awake and underwent transesophageal echocardiography experienced an increase in systolic blood pressure, so transesophageal echocardiography has a potential risk of causing a sudden rupture and cardiac tamponade in patients with type A AD (30). Moreover, cardiovascular surgeons at our institution hesitate to perform an emergency surgical operation on the basis of the findings from only transesophageal echocardiography: They require the most definitive images of the whole aorta, such as those provided with CT.
The patient population in our study and in that of Zeman et al (11) differ, because we selected 57 individuals with surgical proof of dissection, and they selected 23 patients who had chest pain or an abnormal chest radiograph and who were suspected of having dissection. Although we were able to evaluate the accuracy of helical CT in the presence of dissection, the accuracy of helical CT in helping to differentiate normal aortas from those with dissection could not be determined.
Recent advances in CT technology, such as multi–detector row helical CT, may allow imaging of the whole volume of the aorta in a single continuous acquisition. The major advantages of this new technology are faster speed, versatility, and isotropic spatial resolution (31,32). Multi–detector row CT may be a popular examination for the detection of AD or IMH in the near future. We are currently evaluating all types of AD by using multi–detector row CT with long length coverage of the aorta.
In conclusion, helical CT proved to be highly accurate in the evaluation of acute type A AD and IMH; it provided all the important information required for surgery.
|
ACKNOWLEDGMENTS
|
|---|
The authors thank Mitsuru Mori, MD, PhD, for his insightful discussion and assistance in the statistical analysis in this manuscript.
|
FOOTNOTES
|
|---|
Abbreviations: AD = aortic dissection,
IMH = intramural hematoma
Author contributions: Guarantors of integrity of entire study, S.Y., M.H.; study concepts, S.Y., T.A.; study design, S.Y., K.M.; literature research, S.Y., N.Y.; clinical studies, S.Y., H.A., M.T., N.Y., K.M.; data acquisition, S.Y., M.T., N.Y.; data analysis/interpretation, S.Y.; statistical analysis, S.Y., H.A.; manuscript preparation, S.Y.; manuscript definition of intellectual content, T.A., K.M.; manuscript editing, S.Y., M.H.; manuscript revision/review and final version approval, all authors.
|
REFERENCES
|
|---|
- Pretre R, von Segesser LK. Aortic dissection. Lancet 1997; 349:1461-1464.[CrossRef][Medline]
- Daily PO, Trueblood HW, Stinson EB, Wuerflein RD, Shumway NE. Management of acute aortic dissection. Ann Thorac Surg 1970; 10:237-247.[Medline]
- Anagnostopoulos CE, Prabhakar MJ, Kittle CF. Aortic dissections and dissecting aneurysms. Am J Cardiol 1972; 30:263-273.[CrossRef][Medline]
- Yamada T, Tada S, Harada J. Aortic dissection without intimal rupture: diagnosis with MR imaging and CT. Radiology 1988; 168:347-352.[Abstract/Free Full Text]
- Sueyoshi E, Matuoka Y, Sakamoto I, Uetani M, Hayashi K, Narimatsu M. Fate of intramural hematoma of the aorta: CT evaluation. J Comput Assist Tomogr 1997; 21:931-938.[CrossRef][Medline]
- Murray JG, Manisali M, Flamm SD, et al. Intramural hematoma of the thoracic aorta: MR image findings and their prognostic implications. Radiology 1997; 204:349-355.[Abstract/Free Full Text]
- Nienaber CA, von Kodolitsch Y, Petersen B, et al. Intramural hemorrhage of the thoracic aorta: diagnostic and therapeutic implications. Circulation 1995; 92:1465-1472.[Abstract/Free Full Text]
- Maraj R, Rerkpattanapipat P, Jacobs LE, Makornwattana P, Kotler MN. Meta-analysis of 143 reported cases of aortic intramural hematoma. Am J Cardiol 2000; 86:664-668.[CrossRef][Medline]
- Novelline RA, Rhea JT, Rao PM, Stuk JL. Helical CT in emergency radiology. Radiology 1999; 213:321-339.[Abstract/Free Full Text]
- Costello P, Ecker CP, Tello R, Hartnell GG. Assessment of the thoracic aorta by spiral CT. AJR Am J Roentgenol 1992; 158:1127-1130.[Abstract/Free Full Text]
- Zeman RK, Berman PM, Silverman PM, et al. Diagnosis of aortic dissection: value of helical CT with multiplanar reformation and three-dimensional rendering. AJR Am J Roentgenol 1995; 164:1375-1380.[Abstract/Free Full Text]
- Sommer T, Fehske W, Holzknecht N, et al. Aortic dissection: a comparative study of diagnosis with spiral CT, multiplanar transesophageal echocardiography, and MR imaging. Radiology 1996; 199:347-352.[Abstract/Free Full Text]
- Quint LE, Francis IR, Williams DM, et al. Evaluation of thoracic aortic disease with the use of helical CT and multiplanar reconstruction: comparison with surgical findings. Radiology 1996; 201:37-41.[Abstract/Free Full Text]
- Chung JW, Park JH, Im JG, et al. Spiral CT angiography of the thoracic aorta. RadioGraphics 1996; 16:811-824.[Abstract]
- Sebastia C, Pallisa E, Quiroga S, et al. Aortic dissection: diagnosis and follow-up with helical CT. RadioGraphics 1999; 19:45-60.[Abstract/Free Full Text]
- Ledbetter S, Stuk JL, Kaufman JA. Helical (spiral) CT in the evaluation of emergent thoracic aortic syndromes: traumatic aortic rupture, aortic aneurysm, aortic dissection, intramural hematoma, and penetrating atherosclerotic ulcer. Radiol Clin North Am 1999; 37:575-589.[CrossRef][Medline]
- Gross SC, Barr I, Eyler WR, Khaja F, Goldstein S. Computed tomography in dissection of the thoracic aorta. Radiology 1980; 136:135-139.[Abstract/Free Full Text]
- Godwin JD, Breiman RS, Speckman JM. Problems and pitfalls in the evaluation of thoracic aortic dissection by computed tomography. J Comput Assist Tomogr 1982; 6:750-756.[Medline]
- Vasile N, Mathieu D, Keita K, Lellouche D, Bloch G, Cachera JP. Computed tomography of thoracic aortic dissection: accuracy and pitfalls. J Comput Assist Tomogr 1986; 10:211-215.[Medline]
- Erbel R, Engberding R, Daniel W, Roelandt J, Visser C, Rennollet H. Echocardiography in diagnosis of aortic dissection. Lancet 1989; 1:457-461.[Medline]
- Cigarroa JE, Isselbacher EM, DeSanctis RW, Eagle KA. Diagnostic imaging in the evaluation of suspected aortic dissection: old standards and new directions. N Engl J Med 1993; 328:35-43.[Free Full Text]
- Nienaber CA, von Kodolitsch Y, Nicolas V, et al. The diagnosis of thoracic aortic dissection by noninvasive imaging procedures. N Engl J Med 1993; 328:1-9.[Abstract/Free Full Text]
- Loubeyre P, Angelie E, Grozel F, Abidi H, Minh VA. Spiral CT artifact that simulates aortic dissection: image reconstruction with use of 180 degrees and 360 degrees linear-interpolation algorithms. Radiology 1997; 205:153-157.[Abstract/Free Full Text]
- Qanadli SD, El Hajjam M, Mesurolle B, et al. Motion artifact of the aorta simulating aortic dissection on spiral CT. J Comput Assist Tomogr 1999; 23:1-6.[CrossRef][Medline]
- Baque-Juston MC, Wells AU, Hansell DM. Pericardial thickening or effusion in patients with pulmonary hypertension: a CT study. AJR Am J Roentgenol 1999; 172:361-364.[Abstract/Free Full Text]
- Lee R, Maughan RE, Svensson LG. Elephant trunk reconstruction for aberrant right subclavian and aortic aneurysm. Ann Thorac Surg 1997; 64:547-548.[Abstract/Free Full Text]
- Kawamoto S, Bluemke DA, Fishman EK. Aortic dissection involving an aberrant right subclavian artery: CT and MR findings. J Comput Assist Tomogr 1998; 22:918-921.[CrossRef][Medline]
- Rizzo RJ, Aranki SF, Aklog L, et al. Rapid noninvasive diagnosis and surgical repair of acute ascending aortic dissection. J Thorac Cadiovasc Surg 1994; 108:567-575.[Abstract/Free Full Text]
- Geibel A, Kasper W, Behroz A, Przewolka U, Meinertz T, Just H. Risk of transesophageal echocardiography in awake patients with cardiac diseases. Am J Cardiol 1988; 62:337-339.[CrossRef][Medline]
- Silvey SV, Stoughton TL, Pearl W, Collazo WA, Belbel RJ. Rupture of the outer partition of aortic dissection during transesophageal echocardiography. Am J Cardiol 1991; 68:286-287.[CrossRef][Medline]
- Hu H, He HD, Foley WD, Fox SH. Four multidetector-row helical CT: image quality and volume coverage speed. Radiology 2000; 215:55-62.[Abstract/Free Full Text]
- Dawson P, Lees WR. Multi-slice technology in computed tomography. Clin Radiol 2001; 56:302-309.[CrossRef][Medline]
This article has been cited by other articles:
|
|
|
|
 
J. D. Dodd, S. Kalva, A. Pena, F. Bamberg, M. D. Shapiro, S. Abbara, R. C. Cury, T. J. Brady, and U. Hoffmann
Emergency Cardiac CT for Suspected Acute Coronary Syndrome: Qualitative and Quantitative Assessment of Coronary, Pulmonary, and Aortic Image Quality
Am. J. Roentgenol.,
September 1, 2008;
191(3):
870 - 877.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M R Jones and J H Reid
Emergency chest radiology: thoracic aortic disease and pulmonary embolism
Imaging,
September 1, 2006;
18(3):
122 - 138.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
T. Shiga, Z. Wajima, C. C. Apfel, T. Inoue, and Y. Ohe
Diagnostic Accuracy of Transesophageal Echocardiography, Helical Computed Tomography, and Magnetic Resonance Imaging for Suspected Thoracic Aortic Dissection: Systematic Review and Meta-analysis.
Arch Intern Med,
July 10, 2006;
166(13):
1350 - 1356.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
V. D. Raptopoulos, P. B. Boiselle, N. Michailidis, J. Handwerker, A. Sabir, J. A. Edlow, I. Pedrosa, and J. B. Kruskal
MDCT Angiography of Acute Chest Pain: Evaluation of ECG-Gated and Nongated Techniques
Am. J. Roentgenol.,
June 1, 2006;
186(6_Supplement_2):
S346 - S356.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
R. G. Hayter, J. T. Rhea, A. Small, F. S. Tafazoli, and R. A. Novelline
Suspected Aortic Dissection and Other Aortic Disorders: Multi-Detector Row CT in 373 Cases in the Emergency Setting
Radiology,
March 1, 2006;
238(3):
841 - 852.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
H. Alkadhi, S. Wildermuth, L. Desbiolles, T. Schertler, D. Crook, B. Marincek, and T. Boehm
Vascular Emergencies of the Thorax after Blunt and Iatrogenic Trauma: Multi-Detector Row CT and Three-dimensional Imaging
RadioGraphics,
September 1, 2004;
24(5):
1239 - 1255.
[Abstract]
[Full Text]
[PDF]
|
|
|
TOP
ABSTRACT
INTRODUCTION
